1. Field of the Invention
The present invention relates to a fire sensor and a fire sensor status information acquisition system installed in various monitored spaces of various portions of a building, for announcing the outbreak of fire if smoke is detected, for example, and particularly to a fire sensor and a fire sensor status information acquisition system, for transmitting sensitivity information constituting one type of status information.
2. Description of the Related Art
Conventional fire sensors, such as that described in Japanese Patent Laid-Open No. HEI 7-262467 (Gazette), for example, are connected to fire signal receivers by means of signal lines, and if a fire is detected, fire signals are output such that the fire signal receivers perform required fire alarm operations. As a method for receiving status information from fire sensors of this kind, in the case of systems communicating with the fire signal receivers using signal transmissions, if a call signal is received from a signal receiver, a transmitted signal in which the sensitivity data are encoded is sent back to the signal receiver and transmitted externally by making an infrared transmission indicator lamp emit light in response to data “zeros” and “ones” transmitted to the signal receiver.
In other conventional fire sensors, such as that described in U.S. Pat. No. 6,469,623 (Specifications), for example, sensitivity data from a smoke detector is transmitted externally by periodically making a light-emitting diode (LED) emit light using an encoded transmission signal.
However, in these conventional fire sensors, because the sensitivity data from detecting elements are encoded and transmitted externally by making a transmission indicator lamp, or an LED, etc., emit light, one problem has been that the number of light emissions by the transmission indicator lamp, the LED, etc., is extremely high, increasing electric power consumption.
In fire sensing systems, because fire sensors of this kind are installed in various monitored spaces inside a building, large numbers of fire sensors must be installed, and because electric power consumption by the system as a whole is large, there is demand for the electric power consumption of individual fire sensors to be reduced.
In conventional fire sensors such as that described in U.S. Pat. No. 5,721,529 (Specifications), warning threshold values and sensitivity limits are stored in a storage means in advance, and if output is outside the warning threshold values and sensitivity limits, an out-of-bounds signal is generated.
However, when a worker inspects the sensitivity status of such a conventional fire sensor using terminal equipment, the worker must receive a signal transmitted by the fire sensor with the terminal equipment, and inspect the sensitivity status of the fire sensor based on displayed contents displayed on the terminal equipment. The worker can only ascertain abnormal sensitivity of the fire sensor from the displayed contents on the terminal equipment, and one problem has been that it is difficult to arrive at a decision as to whether abnormal sensitivity has actually arisen in the fire sensor.
In conventional fire sensing apparatuses such as that described in U.S. Pat. No. 6,326,880 (Specifications), for example, an automatic test is performed on a fire sensor by admitting radiant energy such as light, etc., into the fire sensor from a tester.
However, in such conventional fire sensing apparatuses, information signals such as the sensitivity data of the detecting elements, etc., are constantly transmitted by a signal transmitting element in the fire sensor. Thus, one problem has been that operations relating to information acquisition for transmission must be performed by the fire sensor continuously, increasing power consumption.